Search results for: virtual active power filter

Authors: Sharapat Sharapat

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English language is perceived as cultural capital in many non-native English-speaking countries, and minority groups in these social contexts seem to invest in the language to be empowered and reposition themselves from the imbalanced power relation with the dominant group. This study is devoted to explore how English learning influence minority Kazakh students’ identity (re)construction at Chinese universities from the scope of ‘imagined community, investment, and identity’ theory of Norton (2013). To this end the three research questions were designed as follows: 1) Kazakh minority students’ English learning experiences at Chinese universities; 2) Kazakh minority students’ views about benefits and opportunities of English learning; 3) the influence of English learning on Kazakh minority students’ identity (re)construction. The study employs an interview-based qualitative research method by interviewing nine Kazakh minority students in universities in Xinjiang and other inland cities in China. The findings suggest that through English learning, some students have reconstructed multiple identities as multicultural and global identities, which created ‘a third space’ to break limits of their ethnic and national identities and confused identity as someone in-between. Meanwhile, most minority students were empowered by the English language to resist inferior or marginalized positions and reconstruct imagined elite identity. However, English learning disempowered students who have little previous English education in school and placed them on unequal footing with other students, which further escalated the educational inequities.

Keywords: minority in China, identity construction, multilingual education, language empowerment

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Authors: Deike Janssen

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In the scenery of the Tyrolean mountains, at an altitude of 1300 meters, stands a building. Residents and activists call it a prison. However, it is not a prison -according to authorities, it is a 'Return Counseling Facility' where migrants and refugees should be "motivated" to return "voluntary" to their countries of origin. This paper argues that the geographical location of the camp functions as a site of exclusion, isolation, and coercion where no one can decide “voluntary” to return, but where people are brought to despair to leave Austria. Through a qualitative case study, this paper documents the heavy impact of offshore detention on the mental, physical and social state of the residents and a variety of human rights problems in the centre. Different developments at the Return Counselling Facility and the law that back up the centre uncover a worrying dynamic that deliberately accepts human rights problems in order to enforce borders, a policy that disregards humanitarian, legal, and ethical stands in order to deport people at all hazards. It, therefore, can be seen as a creative and ultimate exercise of state power, which uses isolated locations to control migration. While the analysis revises the micro and macro implications of the facility and, therefore, the legal and political facets, it also sheds light on the role of the civil society, which tries to increase through constant and collective efforts the human rights efforts of the government.

Keywords: deportation, human rights, migration, refugee detention, voluntary return

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Authors: Yogish Huchaiah, Chandrashekara Krishnappa

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This study considers the optimization and validation of experimental results using Multi-Functional Criteria Technique (MFCT). MFCT is concerned with structuring and solving decision and planning problems involving multiple variables. Production of biodiesel from Composite Oil Methyl Esters (COME) of Jatropha and Pongamia oils, mixed in various proportions and Biodiesel thus obtained from two step transesterification process were tested for various Physico-Chemical properties and it has been ascertained that they were within limits proposed by ASTME. They were blended with Petrodiesel in various proportions. These Methyl Esters were blended with Petrodiesel in various proportions and coded. These blends were used as fuels in a computerized CI DI engine to investigate Performance and Emission characteristics. From the analysis of results, it was found that 180MEM4B20 blend had the maximum Performance and minimum Emissions. To validate the experimental results, MFCT was used. Characteristics such as Fuel Consumption (FC), Brake Power (BP), Brake Specific Fuel Consumption (BSFC), Brake Thermal Efficiency (BTE), Carbon dioxide (CO2), Carbon Monoxide (CO), Hydro Carbon (HC) and Nitrogen oxide (NOx) were considered as dependent variables. It was found from the application of this method that the optimized combination of Injection Pressure (IP), Mix and Blend is 178MEM4.2B24. Overall corresponding variation between optimization and experimental results was found to be 7.45%.

Keywords: COME, IP, MFCT, optimization, PI, PN, PV

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Authors: Zohra Salim

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Objective: To access the relationship of primary tumor thickness with cervical lymphadenopathy in squamous cell carcinoma of buccal mucosa. Methodology: A cross-sectional observational study was carried out on 80 Patients with biopsy-proven oral squamous cell carcinoma of buccal mucosa at Dow University of Health Sciences. All the study participants were treated with wide local excision of the primary tumor with elective neck dissection. Patients with prior head and neck malignancy or those with prior radiotherapy or chemotherapy were excluded from the study. Data was entered and analyzed on SPSS 21. Chi-squared test with 95% C.I and 80% power of the test was used to evaluate the relationship of tumor depth with cervical lymph nodes. Results: 50 participants were male, and 30 patients were female. 30 patients were in the age range of 20-40 years, 36 patients in the range of 40-60 years, while 14 patients were beyond age 60 years. Tumor size ranged from 0.3cm to 5cm with a mean of 2.03cm. Tumor depth ranged from 0.2cm to 5cm. 20% of the participants reported with tumor depth greater than 2.5cm, while 80% of patients reported with tumor depth less than 2.5cm. Out of 80 patients, 27 reported with negative lymph nodes, while 53 patients reported with positive lymph nodes. Conclusion: Our study concludes that relationship exists between the depth of primary tumor and cervical lymphadenopathy in squamous cell carcinoma of buccal mucosa.

Keywords: squamous cell carcinoma, tumor depth, cervical lymphadenopathy, buccal mucosa

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Authors: T. Hadj Sadok, R. Hattab Bey, K. Rebiha

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The valuation of juice from prickly pear of Opuntia ficus indica inermis as cocktails appears an attractive alternative because of their nutritional intake and functional compound has anti-radical activity (polyphenols, vitamin C, carotenoids, Betalaines, fiber and minerals). The juice from the fruit pulp is characterized by a high pH 5.85 which makes it difficult for its conservation and preservation requires a thermal treatment at high temperatures (over 100 °C) harmful for bioactive constituents compared to juice orange more acidic and processed at temperatures < 100 °C. The valuation as fig cocktails-orange is particularly interesting thanks to the contribution of polyph2nols, fiber, vitamin C, reducing sugar (sweetener) and betalaine, minerals while allowing lower temperature processing to decrease pH. The heat treatment of these juices: orange alone or in cocktails showed that the antioxidant power decreases by 12% in presence of 30% of juice treated by the heat and of 28 and 32% in the presence of 10 and 20% juice which shows the effect prickly pear juice of Opuntia. During storage for 4 weeks the loss of vitamin C is 40 and 38% in the presence of 10 and 20% juice and 33% in the presence of 30% pear juice parallel, a treatment of stabilization by heat affects relatively the polyphenols rate which decreases from 10.5% to 30% in the cocktail, and 6.11-6.71pour cocktails at 10% and 20%. Vitamin C decreases to 12 to 24 % after a heat treatment at 85°C for 30 minutes respectively for the orange juice and pear juice; this reduction is higher when the juice is in the form of cocktails composed of 10 to 30 % pear juice.

Keywords: prickly pear juice, orange cocktail, polyphenol, Opuntia ficus indica, vitamin

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Authors: Tijjani Bashir Musa

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The recent global crisis which suddenly results to Nigerian stock market crash revealed some peculiarities of Nigerian firms. Some firms in Nigeria are performing but their stock prices are not increasing while some firms are at the brink of collapse but their stock prices are increasing. Thus, this study examines the relationship between firm performance and stock price in Nigeria. The study covered the period of 2005 to 2009. This period is the period of stock boom and also marked the period of stock market crash as a result of global financial meltdown. The study is a panel study. A total of 140 firms were sampled from 216 firms listed on the Nigerian Stock Exchange (NSE). Data were collected from secondary source. These data were divided into four strata comprising the most performing stock, the least performing stock, most performing firms and the least performing firms. Each stratum contains 35 firms with characteristic of most performing stock, most performing firms, least performing stock and least performing firms. Multiple linear regression models were used to analyse the data while statistical/econometrics package of Stata 11.0 version was used to run the data. The study found that, relationship exists between selected firm performance parameters (operating efficiency, firm profit, earning per share and working capital) and stock price. As such firm performance gave sufficient information or has predictive power on stock prices movements in Nigeria for all the years under study.. The study recommends among others that Managers of firms in Nigeria should formulate policies and exert effort geared towards improving firm performance that will enhance stock prices movements.

Keywords: firm, Nigeria, performance, stock price

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Authors: Yu-Chen Hsu, Kuang C. Lin

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The artificial lung called extracorporeal membrane oxygenation (ECMO) is an important medical machine that supports persons whose heart and lungs dysfunction. Previously, investigation of steady deoxygenated blood flows passing through hollow fibers for oxygen transport was carried out experimentally and computationally. The present study computationally analyzes the effect of biological pulsatile flow on the oxygen transport in blood. A 2-D model with a pulsatile flow condition is employed. The power law model is used to describe the non-Newtonian flow and the Hill equation is utilized to simulate the oxygen saturation of hemoglobin. The dimensionless parameters for the physical model include Reynolds numbers (Re), Womersley parameters (α), pulsation amplitudes (A), Sherwood number (Sh) and Schmidt number (Sc). The present model with steady-state flow conditions is well validated against previous experiment and simulations. It is observed that pulsating flow amplitudes significantly influence the velocity profile, pressure of oxygen (PO2), saturation of oxygen (SO2) and the oxygen mass transfer rates (m ̇_O2). In comparison between steady-state and pulsating flows, our findings suggest that the consideration of pulsating flow in the computational model is needed when Re is raised from 2 to 10 in a typical range for flow in artificial lung.

Keywords: artificial lung, oxygen transport, non-Newtonian flows, pulsating flows

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Authors: Elchin Hajiyev, Afet Memmedova Dadash, Sabina Hajiyeva, Aynur Karimova, Ramiz Aliyev

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Although potatoes have a wide distribution range, the yield potential of varieties varies greatly depending on the region. Our country is made up of agricultural regions with very different environmental characteristics.In this case, we cannot expect the introduced varieties to show the same adaptation to the different conditions of our country. For this reason, in our country, varieties with high general adaptability should be used, rather than varieties with special adaptability in certain areas. Soil salinization has become a global problem.Increased salinity has a serious impact on food security by reducing plant productivity. Plants have protective mechanisms of adaptation to salt stress, such as the synthesis of physiologically active substances, resistance to antioxidant stress and oxidation of membrane lipids. One of these substances is free proline. Our study revealed genetic variation in proline accumulation among samples exposed to stress factors.Changes in proline content under stress conditions were studied in 50 samples. There was wide variation across all treatments.The amount of proline varied between 7.2–37.7 μM/g under salinity conditions.The lowest rate was in the SF33 genotype (1.5 times more than the control (2.5 μM/g)).The highest level of proline under the influence of salt stress was in the SF45 genotype (7.25 times higher than the control (32.5 μM/g)). Our studies have found that the protective system reacts differently to the influence of stress factors. According to the results obtained on the amount of proline, adaptation mechanisms must be more actively activated to maintain metabolism and ensure viability in sensitive forms under the influence of stress factors. At high doses of the salt stressor, a tenfold increase in proline compared to the control indicates significant damage to the plant organism as a result of stress.To prevent damage to the body, the antioxidant system needs to quickly mobilize and work at full capacity in adverse conditions. An increase in the dose of the stress factor salt in our study caused a greater increase in the amount of free proline in plant tissues. Considering the functions of proline as an osmoprotector and antioxidant, it was found that increasing its amount is aimed at protecting the plant from the acute effects of stressors.

Keywords: genetic variability, potato, genotypes, proline, stress

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Authors: S. Ben Fredj, H. Ghali, M. Ben Rejeb, S. Layouni, S. Khefacha, L. Dhidah, H. Said

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Background: The Intensive Care Unit (ICU) provides continuous care and uses a high level of treatment technologies. Although developed country hospitals allocate only 5–10% of beds in critical care areas, approximately 20% of nosocomial infections (NI) occur among patients treated in ICUs. Whereas in the developing countries the situation is still less accurate. The aim of our study is to assess mortality rates in ICUs and to determine its predictive factors. Methods: We carried out a nested case-control study in a 630-beds public tertiary care hospital in Eastern Tunisia. We included in the study all patients hospitalized for more than two days in the surgical or medical ICU during the entire period of the surveillance. Cases were patients who died before ICU discharge, whereas controls were patients who survived to discharge. NIs were diagnosed according to the definitions of ‘Comité Technique des Infections Nosocomiales et les Infections Liées aux Soins’ (CTINLIS, France). Data collection was based on the protocol of Rea-RAISIN 2009 of the National Institute for Health Watch (InVS, France). Results: Overall, 301 patients were enrolled from medical and surgical ICUs. The mean age was 44.8 ± 21.3 years. The crude ICU mortality rate was 20.6% (62/301). It was 35.8% for patients who acquired at least one NI during their stay in ICU and 16.2% for those without any NI, yielding an overall crude excess mortality rate of 19.6% (OR= 2.9, 95% CI, 1.6 to 5.3). The population-attributable fraction due to ICU-NI in patients who died before ICU discharge was 23.46% (95% CI, 13.43%–29.04%). Overall, 62 case-patients were compared to 239 control patients for the final analysis. Case patients and control patients differed by age (p=0,003), simplified acute physiology score II (p < 10-3), NI (p < 10-3), nosocomial pneumonia (p=0.008), infection upon admission (p=0.002), immunosuppression (p=0.006), days of intubation (p < 10-3), tracheostomy (p=0.004), days with urinary catheterization (p < 10-3), days with CVC ( p=0.03), and length of stay in ICU (p=0.003). Multivariate analysis demonstrated 3 factors: age older than 65 years (OR, 5.78 [95% CI, 2.03-16.05] p=0.001), duration of intubation 1-10 days (OR, 6.82 [95% CI, [1.90-24.45] p=0.003), duration of intubation > 10 days (OR, 11.11 [95% CI, [2.85-43.28] p=0.001), duration of CVC 1-7 days (OR, 6.85[95% CI, [1.71-27.45] p=0.007) and duration of CVC > 7 days (OR, 5.55[95% CI, [1.70-18.04] p=0.004). Conclusion: While surveillance provides important baseline data, successful trials with more active intervention protocols, adopting multimodal approach for the prevention of nosocomial infection incited us to think about the feasibility of similar trial in our context. Therefore, the implementation of an efficient infection control strategy is a crucial step to improve the quality of care.

Keywords: intensive care unit, mortality, nosocomial infection, risk factors

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Authors: Elmo Thiago Lins Cöuras Ford, Valentina Alessandra Carvalho do Vale

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The sun is an inexhaustible source and harnessing its potential both for heating and for power generation is one of the most promising and necessary alternatives, mainly due to environmental issues. However, it should be noted that this has always been present in the generation of energy on the planet, only indirectly, as it is responsible for virtually all other energy sources, such as: Generates the evaporation source of the water cycle, which allows the impoundment and the consequent generation of electricity (hydroelectricity); Winds are caused by large-scale atmospheric induction caused by solar radiation; Oil, coal and natural gas were generated from waste plants and animals that originally obtained the energy needed for its development of solar radiation. Thus, the idea of using solar energy for practical purposes for the benefit of man is not new, as it accompanies the story since the beginning of time, which means that the sun was always of utmost importance in the design of shelters, or homes is, constructed by taking into consideration the use of sunlight, practicing what was being lost through the centuries, until a time when the buildings started to be designed completely independent of the sun. However, the climatic rigors still needed to be fought, only artificially and today seen as unsustainable, with additional facilities fueled by energy consumption. This paper presents a study on the feasibility of using solar energy for heating water in homes, developing a simplified methodology covering the mode of operation of solar water heaters, solar potential existing alternative systems of Brazil, the international market, and barriers encountered.

Keywords: solar energy, solar heating, solar project, water heating

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Authors: O. Antypenko, I. Vasilieva, S. Kovalenko

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Investigations for new effective and less toxic antimicrobials agents are always up-to-date. The tetrazole derivatives are quite interesting objects as for synthesis as well as for pharmacological screening. Thus, some derivatives of tetrazole demonstrated antimicrobial activity, namely 5-phenyl-tetrazolo[1,5-c]quinazoline was effective one against Staphylococcus aureus and Esherichia faecalis (MIC = 250 mg/L). Besides, investigation of the 9-bromo(chloro)-5-morpholin(piperidine)-4-yl-tetrazolo[1,5-c]quinazoline’s antimicrobial activity against Esherichia coli and Enterococcus faecalis, Pseudomonas aeruginosa and Staphylococcus aureus revealed that sensitivity of Gram-positive bacteria to the compounds was higher than that of Gram-negative bacteria. So, our previously synthesized, 31 derivatives of 1-(2-(1H-tetrazol-5-yl)-R1-phenyl)-3-R2-phenyl(ethyl)ureas were decided to test for their in vitro antibacterial activity against Gram-positive bacteria (Staphylococcus aureus ATCC 25923, Enterobacter aerogenes, Enterococcus faecalis ATCC 29212), Gram-negative bacteria (Pseudomonas aeruginosa ATCC 9027, Escherichia coli ATCC 25922, Klebsiella pneumoniae 68) and antifungal properties against Candida albicans ATCC 885653. Agar-diffusion method was used for determination of the preliminary activity compared to well-known reference antimicrobials. All the compounds were dissolved in DMSO at a concentration of 100 μg/disk, using inhibition zone diameter (IZD, mm) as a measure for the antimicrobial activity. The most active turned to be 3 structures, that inhibited several bacterial strains: 1-ethyl-3-(5-fluoro-2-(1H-tetrazol-5-yl)phenyl)urea (1), 1-(4-bromo-2-(1H-tetrazol-5-yl)-phenyl)-3-(4-(trifluoromethyl)phenyl)urea (2) and 1-(4-chloro-2-(1H-tetrazol-5-yl)phenyl)-3-(3-(trifluoromethyl)phenyl)urea (3). IZM (mm) was 40 (Escherichia coli), 25 (Klebsiella pneumonia) for compound 1; 12 (Pseudomonas aeruginosa), 15 (Staphylococcus aureus), 10 (Enterococcus faecalis) for compound 2; 25 (Staphylococcus aureus), 15 (Enterococcus faecalis) for compound 3. The most sensitive to the activity of the substances were Gram-negative bacteria Pseudomonas aeruginosa. While none of compound effected on Candida albicans. Speaking about, reference drugs: Amikacin (30 µg/disk) showed 27 and Ceftazide (30 µg/disk) 25 against Pseudomonas aeruginosa. That is, unfortunately, higher than studied 1-(2-(1H-tetrazol-5-yl)-R1-phenyl)-3-R2-phenyl(ethyl)ureas. Obtained results will be used for further purposeful optimization of the leading compounds in the more effective antimicrobials because of the ever-mounting problem of microorganism’s resistance.

Keywords: antimicrobial, antifungal, compounds, 1-(2-(1H-tetrazol-5-yl)-R1-phenyl)-3-R2-phenyl(ethyl)ureas

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Authors: Dong Il Shim, Geehong Choi, Donghwi Lee, Namkyu Lee, Hyung Hee Cho

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Effective cooling technology is required to secure thermal stability in extreme heat generated systems such as integrated electronic devices and power generated systems. Pool boiling heat transfer is one of the powerful cooling mechanisms using phase change phenomena. Critical heat flux (CHF) and heat transfer coefficient (HTC) are main factors to evaluate the performance of boiling heat transfer. CHF is the limitation of boiling heat transfer before film boiling which occurs thermal failure. Surface wettability is an important surface characteristic of boiling heat transfer. A hydrophilic surface has higher CHF through effective working fluid supply to local hot spots. A hydrophobic surface promotes the onset of nucleate boiling (ONB) to enhance HTC. In this study, superbiphilic surfaces, which is combined with superhydrophillic and superhydrophobic, are applied on boiling experiments to maximize boiling performance. We conducted pool boiling heat transfer using DI water at a saturated temperature and recorded bubble dynamics using a high-speed camera with 2000 fps. As a result, superbiphilic patterned surfaces promote ONB and enhance both CHF and HTC. This study demonstrates the enhanced boiling performance using superbiphilic surfaces by effective nucleation and separation of liquid/vapor pathway. We expect that further enhancement of heat transfer could be achieved in future work using optimized patterned surfaces.

Keywords: boiling heat transfer, wettability, critical heat flux, heat transfer coefficient

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Authors: Wujian Han

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In the process of human interaction and communication, speech act verbs are considered to be the most active component and the main means for information transmission, and are also taken as an indication of the structure of linguistic behavior. The theoretical value and practical significance of such everyday built-in metalanguage have long been recognized. This paper, which is part of a bigger study, is aimed to provide useful insights for a more precise and systematic application to speech act verbs translation between English and Chinese, especially with regard to the degree to which generic integrity is maintained in the practice of translation of legal documents. In this study, the corpus, i.e. Chinese legal texts and their English translations, English legal texts, ordinary Chinese texts, and ordinary English texts, serve as a testing ground for examining contrastively the usage of English and Chinese directive speech act verbs in legal genre. The scope of this paper is relatively wide and essentially covers all directive speech act verbs which are used in ordinary English and Chinese, such as order, command, request, prohibit, threat, advice, warn and permit. The researcher, by combining the corpus methodology with a contrastive perspective, explored a range of characteristics of English and Chinese directive speech act verbs including their semantic, syntactic and pragmatic features, and then contrasted them in a structured way. It has been found that there are similarities between English and Chinese directive speech act verbs in legal genre, such as similar semantic components between English speech act verbs and their translation equivalents in Chinese, formal and accurate usage of English and Chinese directive speech act verbs in legal contexts. But notable differences have been identified in areas of difference between their usage in the original Chinese and English legal texts such as valency patterns and frequency of occurrences. For example, the subjects of some directive speech act verbs are very frequently omitted in Chinese legal texts, but this is not the case in English legal texts. One of the practicable methods to achieve adequacy and conciseness in speech act verb translation from Chinese into English in legal genre is to repeat the subjects or the message with discrepancy, and vice versa. In addition, translation effects such as overuse and underuse of certain directive speech act verbs are also found in the translated English texts compared to the original English texts. Legal texts constitute a particularly valuable material for speech act verb study. Building up such a contrastive picture of the Chinese and English speech act verbs in legal language would yield results of value and interest to legal translators and students of language for legal purposes and have practical application to legal translation between English and Chinese.

Keywords: contrastive analysis, corpus-based, directive speech act verbs, legal texts, translation between English and Chinese

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Authors: Gheorghe Braniste

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Gender gap has always been in dispute when comparing records and has been a major factor influencing best performances in various sports. Consequently, our study registers the evolution of the difference between men's and women’s best performances within either cyclic or acyclic sports, considering the fact that the training sessions of high performance athletes prove both similarities and differences in long-term adaptation of their body to stress and effort in breaking limits and records. Firstly, for a correct interpretation of the data and tables included in this paper, we must point out that the intense muscular activity has a considerable impact on the structural organization of the organs and systems of the performer's body through the mechanism of motor-visceral reflexes, forming a high working capacity suitable for intense muscular activity. The opportunity to obtaine high sports results during the official competitions is due, on the one hand, to the genetic characteristics of the athlete's body, and on the other hand, to the fact that playing professional sports leaves its mark on the vital morphological and functional parameters. The aim of our research is to study the landmarking differences between male and female athletes and their physical development, together with their growing capacity to stand up to the functional training during the competitive period of their annual training cycle. In order to evaluate the physical development of the athletes, the data of the anthropometric screenings obtained at the Olympic Training Center of the selected teams of the Republic of Moldova were interpreted and rated. During the study of physical development in terms of body height and weight, vital capacity, thoracic excursion, maximum force (Fmax), dynamometry of the hand and back, a further evaluation of the physical development indices that allow an evaluation of complex physical development were registered. The interdependence of the results obtained in performance sports with the morphological and functional particularities of the athletes' body is firmly determined and cannot be disputed. Nevertheless, registered data proved that with the increase of the training capacity, the morphological and functional abilities of the female body increase and, in some respects, approach and even slightly surpass the men in certain sports.

Keywords: physical development, indices, parameters, active body weight, morphological maturity, physical performance

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Authors: Uchechukwu Vincent Okpala

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Under the Sun, energy is a key factor for the sustenance of life and its environment. The need to protect the environment as energy is generated and consumed has called for renewable and green energy sources. To be part of this green revolution, we synthesized and characterized undoped and velvet tamarind doped zinc sulfide (ZnS) crystals using sol-gel methods. Velvet tamarind was whittled down using the top-down approach of nanotechnology. Sodium silicate, tartaric acid, zinc nitrate, and thiourea were used as precursors. The grown samples were annealed at 105°C. Structural, optical, and compositional analyses of the grown samples revealed crystalline structures with varied crystallite sizes influenced by doping. Energy-dispersive X-ray spectroscopy confirmed elemental compositions of Zn, S, C and O in the films. Atomic percentages of the elements varied with VT doping. FT-IR analysis indicated the presence of functional groups like O-H stretching (alcohol), C=C=C stretching (alkene group), C=C bending, C-H stretching (alkane), N-H stretching (aliphatic primary amine) and N=C=S stretching (isothiocyanate) constituent in the film. The transmittance of the samples increased from the visible region to the infrared region making the samples good for poultry and solar energy applications. The bandgap energy of the films decreased as the number of VT drops increased, from 2.4 to 2.2. They were wide band gap materials and were good for optoelectronic, photo-thermal, high temperature, high power and solar cell applications.

Keywords: doping, sol-gel, velvet tamarind, ZnS.

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Authors: Umut Tuğlu Karslı

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While, port function had a major role during the antiquity and medieval times, it has started to lose its significance in 19th century. In many port cities, while heavy industrial functions and ports have been moved out of the former port districts, the resulting derelict spaces have been transformed to new waterfront quarters to accommodate commercial, tourism, cultural, residential and public uses. Primary aim of these operations is to revitalize abandoned spaces of historical potential and re-establish a relationship between the city and the coast. Karakoy Port, field of this study, located in the Bosphorus, was surrounded by the city centre in time due to the transformation of urban functions, and as a result it has lost its former significance. While Karakoy has 24 hours lively residential and commercial uses in old times; in early 1980s, became a district of mechanical, plumbing and electronic parts suppliers during the day and a place for homeless at night. Today, activities for revitalization of this region continue in two forms and scales. First of these activities is the "planned transformation projects," which also includes the most important one “Galataport project”, and the second one is "spontaneous transformation," which consists of individual interventions. Galataport project that based on the idea of arranging the area specifically for tourists was prepared in 2005 and became a topic of tremendous public debate. On the other hand, the "spontaneous transformation" that is observed in the Karakoy District starts in 2004 with the foundation of “Istanbul Modern Museum”. Istanbul Modern, the first contemporary arts museum of the city, allowed the cultural integration of old naval warehouses of the port to the daily life. Following this adaptive reuse intervention, the district started to accommodate numerous art galleries, studios, café-workshops and design stores. In this context, this paper briefly examines revitalization studies in obsolete port regions, analyzes the planned and ongoing socio-spatial transformations in the specific case of Karakoy under the subjects of "planned transformation projects" and "spontaneous transformation", and realizes a critical review of the sustainability of the proposals on how to reinstate the district in the active life of Istanbul.

Keywords: port cities, socio-spatial transformation, urban regeneration, urban revitalization

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Authors: Che Jusoh, Mohd Rahimi, Toby Mundel

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This study was designed to investigate the physiological and performance effects of a local Malaysian native starch (Metroxylin sago) on cycling in a hot (30°C) and humid (78% RH) environment. Eight male, non-heat acclimated, well-trained club cyclists (VO2max 65 ± 10 ml kg-1 min-1, peak aerobic power 397 ± 71 W) completed one familiarization and three experimental trials in our laboratory simulating cycling in environmental conditions of heat and humidity. Each trial consisted of 45 minutes at a fixed workload (55% VO2max) followed by a 15 minute time-trial (~75% VO2max). Sago in porridge form was consumed 1h before exercise (Pre), in gel form during exercise (Dur) and compared to a control trial (Con), using a random, cross-over design. Plasma glucose concentration did not differ between trials (P = 0.06) with an increase from 4.1 ± 0.6 to 6.1 ± 1.6 mmol-1 (Con), 4.8 ± 1.7 to 5.7 ± 0.4 mmol-1 (Pre) and 4.7 ± 0.8 to 6.9 ± 1.4 mmol-1 (Dur) from start to end of exercise. Plasma lactate increased (P = 0.02) from 1.6 ± 0.3 to 7.6 ± 2.2 mmol-1 (Con), 1.7 ± 0.5 to 7.3 ± 2.9 mmol-1 (Pre) and 1.6 ± 0.2 to 7.3 ± 1.8 mmol-1 (Dur) with no effect of trial (P = 0.74). No differences were found between trials for RER (P = 0.328) with values of 0.93 ± 0.05 (Con), 0.94 ± 0.04 (Pre) and 0.92 ± 0.04 (Dur). There were no differences between trials in rectal (P = 0.64) and skin (P = 0.56) temperatures; values reaching 39.1 ± 0.5°C (Con), 38.9 ± 0.4°C (Pre) and 39.1 ± 0.4°C (Dur) for rectal and 32.7 ± 1.2°C (Con), 32.8 ± 1.4°C (Pre) and 32.8 ± 1.8°C (Dur) for skin temperature, respectively. Heart rate (P = 0.07) also did not differ between trials but reached maximal values by the end of time-trial for all trials. Performance was unaffected by trial (P = 0.98) with the average work completed in 15 minutes being 221 ± 33 kJ (Con), 222 ± 31 kJ (Pre) and 219 ± 32 kJ (Dur), respectively. Therefore, the results of this investigation do not support consumption of sago, either before or during exercise, in altering the thermoregulatory, metabolic or performance responses in a hot and humid environment.

Keywords: hot and humid, physiology, time trial performance, thermoregulatory

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Authors: Sonia Saddiqui, Maya Marcus

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UTS STEAMpunk Girls is an educational program for young women (aged 12-16), to empower them to be more informed and active members of the 21st century workforce. With the number of STEM graduates on the decline, especially among young women, an additional aim of the program is to trial a STEAM (Science, Technology, Engineering, Arts/Humanities/Social Sciences, Mathematics), inter-disciplinary approach to improving STEM engagement. In-line with UNESCO’s recent focus on promoting ‘transversal competencies’ in future graduates, the program utilised co-design, project-based learning, entrepreneurial processes, and inter-disciplinary learning. The program consists of two phases. Taking a participatory design approach, the first phase (co-design workshops) provided valuable insight into student perspectives around engaging young women in STEM and inter-disciplinary thinking. The workshops positioned 26 young women from three schools as subject matter experts (SMEs), providing a platform for them to share their opinions, experiences and findings around the STEAM disciplines. The second (pilot) phase put the co-design phase findings into practice, with 64 students from four schools working in groups to articulate problems with real-world implications, and utilising design-thinking to solve them. The pilot phase utilised project-based learning to engage young women in entrepreneurial and STEAM frameworks and processes. Scalable program design and educational resources were trialed to determine appropriate mechanisms for engaging young women in STEM and in STEAM thinking. Across both phases, data was collected via longitudinal surveys to obtain pre-program, baseline attitudinal information, and compare that against post-program responses. Preliminary findings revealed students’ improved understanding of the STEM disciplines, industries and professions, improved awareness of STEAM as a concept, and improved understanding regarding inter-disciplinary and design thinking. Program outcomes will be of interest to high-school educators in both STEM and the Arts, Humanities and Social Sciences fields, and will hopefully inform future programmatic approaches to introducing inter-disciplinary STEAM learning in STEM curriculum.

Keywords: co-design, STEM, STEAM, project-based learning, inter-disciplinary

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Authors: Betsy H. Edwards

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Background: Public Health England recognises unprotected sex and consequent transmission of sexually transmitted infections (STIs) as significant problems within student populations. Government surveys show that 50% of sexually-active young adults engage in unprotected sex with new partners, with 10% never using condoms. The recent Channel Four mini-series ‘It’s a Sin’ dramatises the 1980s AIDS epidemic and has been praised for its educational value and for promoting safe sexual practices to its viewers. This mixed-methods questionnaire study aims to investigate whether the series can change attitudes towards safe sex in student populations, can promote the use of condoms in student populations, and whether television, in general, is a useful tool for promoting health education. Methods: A questionnaire, created on Microsoft Forms, was distributed to students at the University of Birmingham via Facebook groups between September 2021 and May 2022. To consent, participants had to be aged 18 or over, a student at the university, have seen the entire series of ‘It’s a Sin’, and read the study information. Data was confidentially stored within the University’s secured OneDrive in accordance with the study’s approved ethics application. Quantitative questions measured participants’ attitudes and behaviours using Likert scales. Qualitative data was analysed using thematic analysis. Quantitative Results: 78 students completed the questionnaire. 43 participants (55%) felt that the series ‘It’s a Sin’ promoted safe sex. 74 participants (96%) and 31 participants (39%) said they were ‘very likely’ or ‘likely’ to use condoms with a casual partner during penetrative sex and oral sex respectively. 27 participants (35%) felt that watching ‘It’s a Sin’ made them more likely to use condoms; of these 27 participants, all were ‘very likely’ or ‘likely’ to use condoms during penetrative sex, and 9 were ‘very likely’ or ‘likely’ to during oral sex. 49 participants (63%) and 53 participants (68%) felt that television is a good way to provide health education and to promote healthy behaviours respectively. Qualitative Results: 56 participants (72%) gave reasons why the series had been associated with an increased uptake in HIV testing. Three themes emerged: increased education and attention, decreased stigmatisation, and relatability of characters on screen. Conclusions: This study suggests that the series ‘It’s a Sin’ can influence attitudes towards and the uptake of safe sexual practices. It would be useful for further research - using larger, randomised samples - to explore impacts upon populations lesser-educated about sexual health, who potentially have more to gain from watching series such as ‘It’s a Sin’.

Keywords: GUM, It's a sin, media, sexual health, students, television, tv

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Authors: Ishmael Ntlhamu

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In Limpopo Province, the use of herbal concoctions is becoming very popular. These concoctions are claimed to be capable of treating ulcers, diabetes, certain STDs, blood cleansing, and many more types of diseases. The aim of this study was to evaluate the phytochemical composition, evaluate the pharmacological effects and consumption safety in herbal concoctions to treat various kinds of ailments in Limpopo. The concoctions were extracted with 80% acetone. Microorganisms in the concoctions were identified using the Vitek 2 compact system. Qualitative phytochemical analysis was determined using standard chemical tests and thin layer chromatography (TLC). Total polyphenol content was quantified. Antioxidant activity was quantified using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) assay and ferric reducing power. Antimicrobial activities were determined using a broth micro-dilution assay and bioautography. Cell viability assay was used to determine the cytotoxicity. Results showed that concoctions had antioxidant activity. Presence of different phytoconstituents was observed. Isolated microorganisms were identified as Burkholderia pseudomallei, Staphylococcus vitulimus, Enterococcus columbae, Kocuria kristanae, Staphylococcus intermedius, Cryptococcus laurenti. and Burkholderia pseudomallei (highly pathogenic). Therefore, phytochemicals prove that the concoctions can heal as the antimicrobial tests also displayed activity. Moreover, the concoctions did not exhibit cytotoxic effects. However, contaminants raise concerns, not only for consumer safety but also the quality of herbal concoctions available as part of the traditional medicinal practice in Limpopo.

Keywords: antimicrobials, concoctions, cytotoxicity, phytochemicals

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Authors: Mst Shapna Akter, Hossain Shahriar

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Neural network approaches are machine learning methods used in many domains, such as healthcare and cyber security. Neural networks are mostly known for dealing with image datasets. While training with the images, several fundamental mathematical operations are carried out in the Neural Network. The operation includes a number of algebraic and mathematical functions, including derivative, convolution, and matrix inversion and transposition. Such operations require higher processing power than is typically needed for computer usage. Central Processing Unit (CPU) is not appropriate for a large image size of the dataset as it is built with serial processing. While Graphics Processing Unit (GPU) has parallel processing capabilities and, therefore, has higher speed. This paper uses advanced Neural Network techniques such as VGG16, Resnet50, Densenet, Inceptionv3, Xception, Mobilenet, XGBOOST-VGG16, and our proposed models to compare CPU and GPU resources. A system for classifying autism disease using face images of an autistic and non-autistic child was used to compare performance during testing. We used evaluation matrices such as Accuracy, F1 score, Precision, Recall, and Execution time. It has been observed that GPU runs faster than the CPU in all tests performed. Moreover, the performance of the Neural Network models in terms of accuracy increases on GPU compared to CPU.

Keywords: autism disease, neural network, CPU, GPU, transfer learning

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Authors: G. Ghamrawi, Y. Abunnasr, M. Fawaz, S. Yazigi

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Coastal cities are constantly exposed to environmental degradation and economic regression fueled by rapid and uncontrolled urban growth as well as continuous resource depletion. This is the case of the City of Mina in Tripoli (Lebanon), where lack of awareness to preserve social, ecological, and historical assets, coupled with the increasing development pressures, are threatening the socioeconomic status of the city residents, the quality of life and accessibility to the coast. To address these challenges, a holistic coastal urban design and planning approach was developed to analyze the environmental, political, legal, and socioeconomic context of the city. This approach aims to investigate the potential of balancing urban development with the protection and enhancement of cultural, ecological, and environmental assets under an integrated coastal zone management approach (ICZM). The analysis of Mina's different sectors adopted several tools that include direct field observation, interviews with stakeholders, analysis of available data, historical maps, and previously proposed projects. The findings from the analysis were mapped and graphically represented, allowing the recognition of character zones that become the design intervention units. Consequently, the thesis proposes an urban, city-scale intervention that identifies 6 different character zones (the historical fishing port, Abdul Wahab island, the abandoned Port Said, Hammam el Makloub, the sand beach, and the new developable area) and proposes context-specific design interventions that capitalize on the main characteristics of each zone. Moreover, the intervention builds on the institutional framework of ICZM as well as other studies previously conducted for the coast and adopts nature-based solutions with hybrid systems for providing better environmental design solutions for developing the coast. This enables the realization of an all-inclusive, well-connected shoreline with easy and free access towards the sea; a developed shoreline with an active local economy, and an improved urban environment.

Keywords: blue green infrastructure, coastal cities, hybrid solutions, integrated coastal zone management, sustainable development, urban planning

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Authors: Siu-Siu Guo, Qingxuan Shi

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In this paper, single-degree-of-freedom (SDOF) systems to white noise and colored noise excitations are investigated. By expressing colored noise excitation as a second-order filtered white noise process and introducing colored noise as an additional state variable, the equation of motion for SDOF system under colored noise is then transferred artificially to multi-degree-of-freedom (MDOF) system under white noise excitations. As a consequence, corresponding Fokker-Planck-Kolmogorov (FPK) equation governing the joint probabilistic density function (PDF) of state variables increases to 4-dimension (4-D). Solution procedure and computer programme become much more sophisticated. The exponential-polynomial closure (EPC) method, widely applied for cases of SDOF systems under white noise excitations, is developed and improved for cases of systems under colored noise excitations and for solving the complex 4-D FPK equation. On the other hand, Monte Carlo simulation (MCS) method is performed to test the approximate EPC solutions. Two examples associated with Gaussian and non-Gaussian colored noise excitations are considered. Corresponding band-limited power spectral densities (PSDs) for colored noise excitations are separately given. Numerical studies show that the developed EPC method provides relatively accurate estimates of the stationary probabilistic solutions. Moreover, statistical parameter of mean-up crossing rate (MCR) is taken into account, which is important for reliability and failure analysis.

Keywords: filtered noise, narrow-banded noise, nonlinear dynamic, random vibration

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Authors: Nikhil S. Mane, Mukund L. Harugade, Narayan V. Hargude, Vishal P. Patil

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The fluids exposed to magnetic field can enhance the convective heat transfer by inducing secondary convection currents due to Lorentz force. The use of magnetohydrodynamic (MHD) forces in power generation and mass transfer is increasing steadily but its application to enhance the convective currents in fluids needed to be explored. The enhancement in convective heat transfer using MHD forces can be employed in heat exchangers, cooling of molten metal, vapour compression refrigeration (VCR) systems etc. The effective increase in the convective heat transfer without any additional energy consumption will lead to the energy efficient heat exchanging devices. In this work, the effect of MHD forces on the performance of air conditioning system working on the VCR system is studied. The refrigerant in VCR system is exposed to the magnetic field which influenced the flow of refrigerant. The different intensities of magnets are used on the different liquid refrigerants and investigation on performance of split air conditioning system is done under different loading conditions. The results of this research work show that the application of magnet on refrigerant flow has positive influence on the coefficient of performance (COP) of split air conditioning system. It is also observed that with increasing intensity of magnetic force the COP of split air conditioning system also increases.

Keywords: magnetohydrodynamics, heat transfer enhancement, VCRS, air conditioning, refrigeration

Procedia PDF Downloads 185

Authors: Sheila Shahidi

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UV protection by fabrics has recently become a focus of great interest, particularly in connection with environmental degradation or ozone layer depletion. Fabrics provide simple and convenient protection against UV radiation (UVR), but not all fabrics offer sufficient UV protection. To describe the degree of UVR protection offered by clothing materials, the ultraviolet protection factor (UPF) is commonly used. UV-protective fabric can be generated by application of a chemical finish using normal wet-processing methodologies. However, traditional wet-processing techniques are known to consume large quantities of water and energy and may lead to adverse alterations of the bulk properties of the substrate. Recently, usage of plasmas to generate physicochemical surface modifications of textile substrates has become an intriguing approach to replace or enhance conventional wet-processing techniques. In this research work the effect of plasma treatment on UV protection properties of fabrics was investigated. DC magnetron sputtering was used and the parameters of plasma such as gas type, electrodes, time of exposure, power and, etc. were studied. The morphological and chemical properties of samples were analyzed using Scanning Electron Microscope (SEM) and Furrier Transform Infrared Spectroscopy (FTIR), respectively. The transmittance and UPF values of the original and plasma-treated samples were measured using a Shimadzu UV3101 PC (UV–Vis–NIR scanning spectrophotometer, 190–2, 100 nm range). It was concluded that, plasma which is an echo-friendly, cost effective and dry technique is being used in different branches of the industries, and will conquer textile industry in the near future. Also it is promising method for preparation of UV protection textile.

Keywords: fabric, plasma, textile, UV protection

Procedia PDF Downloads 499

Authors: Ashfaque Hossain Khan, Brian Thomson, Ratan Debnath, Abhishek Motayed, Mulpuri V. Rao

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Though the efforts had been made, the problem of cross-sensitivity for a single metal oxide-based sensor can’t be fully eliminated. In this work, a sensor array has been designed and fabricated comprising of platinum (Pt), copper (Cu), and silver (Ag) decorated TiO2 and ZnO functionalized GaN nanowires using industry-standard top-down fabrication approach. The metal/metal-oxide combinations within the array have been determined from prior molecular simulation study using first principle calculations based on density functional theory (DFT). The gas responses were obtained for both single and mixture of NO2, SO2, ethanol, and H2 in the presence of H2O and O2 gases under UV light at room temperature. Each gas leaves a unique response footprint across the array sensors by which precise discrimination of cross-sensitive gases has been achieved. An unsupervised principal component analysis (PCA) technique has been implemented on the array response. Results indicate that each gas forms a distinct cluster in the score plot for all the target gases and their mixtures, indicating a clear separation among them. In addition, the developed array device consumes very low power because of ultra-violet (UV) assisted sensing as compared to commercially available metal-oxide sensors. The nanowire sensor array, in combination with PCA, is a potential approach for precise real-time gas monitoring applications.

Keywords: cross-sensitivity, gas sensor, principle component analysis (PCA), sensor array

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Authors: Marc Arthur Bien Aimé, Julio da Silveira Moreira

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This study examines the political speech in Haiti over the course of the decade 2011-2021, focusing on the speeches of the presidents Michel J. Martelly and Jovenel Moïse and their impacts on their awareness collective. In using a qualitative approach, we have analyzed the speech of the president pronounced in response to the political instability of countries, as well as interviews with a group of 20 Haitians living in Port- Au-Prince. Our results put in evidence their complex relationship between politics, awareness collective, and the influence of the powers imperialists. We show that the situation in Haiti's disastrous social and political situation is driven by personal political interests and the absence of a state political project. Moreover, the speeches of the president’s analysis are meaningless, transforming concepts such as social progress and justice in simple words. This political rhetoric contributes to the domination symbolic of the population of Haitian. This study is also linked to the theme “Constitutions, processes democratic and critical of the state in Latin America,” emphasizing the importance of analysis of political speech to understand the complexities of the democratic process and criticism of the State in their Latin American region. We suggest future research to deepen our understanding of these political dynamics and their impact on public policies and developments of the constitutions throughout Latin America.

Keywords: political discourse, conscience collective, inequality social, democratic processes, constitutions, Haiti

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Authors: Sally Barsoum

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This paper is providing a significant insight into the role of satire in Egyptian politics and how it has been received from the government and viewer’s point of view. It mainly sets out to test whether Bassem Youssef’s satirical program has played a significant role in Egypt recent politics and to investigate what is the nature and extent of this role. In order to test this hypothesis, the researcher chose to critically analyze one episode of Bassem Youssef’s satirical show, El Bernameg. This paper goes further to highlight that the aims of satire is to invite citizens to analyze, criticize and question people in power and the realm of politics rather than remain as untouched subjects by combining humor with critique in order to enhance citizens’ political awareness and perhaps even political engagement. Moreover it identifies that Bassem Youssef’s satire is to use laughter as a medium to communicate his political message. By first informing the public and secondly engaging them through laughter, satire plays a very constructive political role, which have been argued finally that Bassem Youssef has indeed played an important part in the Egyptian political scene of today and this can be measured by the degree of censorship that he has been subject to and the level of international and domestic reaction towards his satirical show. At the end, this paper is suggesting that the measure of a strong government is its ability not only to accommodate satire but also to learn from it.

Keywords: political satirist, Bassem Youssef, capital broadcasting center, TV channel, muslims brotherhood regime, ONTV Egyptian TV channel

Procedia PDF Downloads 298

Authors: Genevieve Jorolan-Quintero

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After the devastation caused by typhoon Haiyan in the southeastern part of the Philippines in 2012, there was this intense need among the indigenous communities to ‘reconcile’ with nature. The belief that the deluge, which claimed thousands of lives, was caused by the destruction of the environment because of humanities’ greed and carelessness was widespread and strong. The rift had to be mended. Nature had to be appeased. For this, the balyan (priestess) was called in to perform a ritual. Only she can communicate with the spirits. The communities depend on her spiritual intervention as she alone has the power to invoke the spirits of nature. Among the indigenous people, the balyan is most often also a magdadawot (bard) who possesses the knowledge especially about the folk epics and the skill to chant them. The balyan is the communities’ repository of knowledge. When one passes away, a whole library of tribal knowledge and wisdom is lost. The oral traditions embody the life values, ideals, customs, and even the history of the First Nations People. These include the myths, epics, legends, riddles, and songs. The indigenous system is patriarchal, but is actually indirectly matriarchal reflecting the authority of the woman. Disputes within the community are heard and tried by the Council of Elders. However, the balyan is often consulted for her opinion. Her advice is deemed significant and most often necessary. These are three instances that highlight the significant role of the balyan among the indigenous communities in the Philippines, especially among the Mandaya tribe who live in the southern region of the country. This paper highlights the unique kind of leadership of the Mandaya woman – as priestess and bard - and her impact on the lives of her people.

Keywords: balyan, bard, magdadawot, mandaya

Procedia PDF Downloads 307

Authors: Krupali Mehta, Sandip Bhatt, Umesh Trivedi, Bhavesh Bharatiya, Mukesh Ranjan, Atindra D. Shukla

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Owing to the dominating surface forces and large-scale surface interactions, the nano-scale particles face difficulties in getting suspended in various media. Magnetic nanoparticles of iron oxide offer a great deal of promise due to their ease of preparation, reasonable magnetic properties, low cost and environmental compatibility. We intend to modify the surface of magnetic Fe₂O₃ nanoparticles with selected surface modifying agents using simple and effective single-step chemical reactions in order to enhance dispersibility of magnetic nanoparticles in non-polar media. Magnetic particles were prepared by hydrolysis of Fe²⁺/Fe³⁺ chlorides and their subsequent oxidation in aqueous medium. The dried particles were then treated with Octadecyl quaternary ammonium silane (Terrasil™), stearic acid and gallic acid ester of stearyl alcohol in ethanol separately to yield S-2 to S-4 respectively. The untreated Fe₂O₃ was designated as S-1. The surface modified nanoparticles were then analysed with Dynamic Light Scattering (DLS), Fourier Transform Infrared spectroscopy (FTIR), X-Ray Diffraction (XRD), Thermogravimetric Gravimetric Analysis (TGA) and Scanning Electron Microscopy and Energy dispersive X-Ray analysis (SEM-EDAX). Characterization reveals the particle size averaging 20-50 nm with and without modification. However, the crystallite size in all cases remained ~7.0 nm with the diffractogram matching to Fe₂O₃ crystal structure. FT-IR suggested the presence of surfactants on nanoparticles’ surface, also confirmed by SEM-EDAX where mapping of elements proved their presence. TGA indicated the weight losses in S-2 to S-4 at 300°C onwards suggesting the presence of organic moiety. Hydrophobic character of modified surfaces was confirmed with contact angle analysis, all modified nanoparticles showed super hydrophobic behaviour with average contact angles ~129° for S-2, ~139.5° for S-3 and ~151° for S-4. This indicated that surface modified particles are super hydrophobic and they are easily dispersible in non-polar media. These modified particles could be ideal candidates to be suspended in oil-based fluids, polymer matrices, etc. We are pursuing elaborate suspension/sedimentation studies of these particles in various oils to establish this conjecture.

Keywords: iron nanoparticles, modification, hydrophobic, dispersion

Procedia PDF Downloads 123